If you do not have an ophthalmologist, or if you are away from home, find a teaching hospital that has a training program in ophthalmology, go to their emergency room, and ask to see the eye resident on call. This chapter describes several examples of each type of eye problem.
During transcription, enzymes called RNA polymerases build RNA molecules that are complementary to a portion of one strand of the DNA double helix (Figure 3). Figure 3: RNA polymerase at work. RNA polymerase (green) synthesizes a strand of RNA that is complementary to the DNA template strand below it.
Rating Newest Oldest. Best Answer: You are used to talk about transcription of DNA INTO mRNA. If you use special enzymes called reverse-transcriptases, you can transcribe mRNA into DNA, which is then called cDNA as complementary DNA. This is not the same of the DNA from which you got the mRNA in the first place, because it does not have introns or regulative regions. In the labs, you make cDNA when you want to analyze mRNA because it is more stable than mRNA itself and it is its exact copy. So you use this instead of mRNA.